To support such high-lift devices and guide them during their deployment, it is also well-known in the art to use tracks fixed to the high-lift device and comprising raceways for contacting rollers or glide pads mounted on the main body of the airfoil.
Besides support and guidance of the movable high-lift devices, transferring aerodynamic loads on the high-lift device to the main body of the airfoil, some tracks may also perform the additional function of transmitting the extension and/or retraction forces from an actuator to the high-lift device. Such driven high-lift device tracks can be actuated by linear or rotational actuators. In the case of a rotational actuator, the track may be driven through a lever and drive link mechanism, or through a rack and pinion mechanism.
One such high-lift device track, driven by a rotational actuator through a rack and pinion mechanism, has been disclosed in US Patent Application Publication US 2007/0102587 A1, which appears to represent the closest prior art. This high-lift device track comprises a first track end comprising attachment points for the high-lift device, two vertical flanges connected by a horizontal web, raceways for guiding rollers or glide pads, and a gear rack installed between said flanges over a first track segment. To accommodate said gear rack between the two vertical flanges, this first track segment presents an inverted-U, or  cross-section.
In order to ensure accurate and smooth operation, i.e. retraction and extension, as well as durability and maintainability of the entire mechanism, tolerances are very tightly controlled at all interfaces between the high-lift device track and the surrounding structure of the main body of the airfoil. Key dimensions are the height and width of the cross section of the high-lift device track, as this envelope has to be guided by the guide rollers and/or glide pads. The width tolerance has to be achieved at the top and bottom of the high-lift device track. For the bottom this means the width tolerance has to be achieved at assembly level, after installation of the gear rack.
However, in the conventional production process the channel between the two vertical flanges is usually machined from a full block or forging. This machining step releases internal stresses, in particular at a second end of the beam, opposite to said first end, which may deflect the flanges beyond the abovementioned width tolerance in a transversal plane. This can lead to complex and time consuming, thus costly, assembly principles and quality assurance procedures, as well as limitations at different manufacturing operations of the slat track component.